Features for a prosthetic wrist and associated methods are described. The wrist couples with a prosthetic socket and a prosthetic hand. The wrist may rotate the hand. The wrist includes features to prevent or mitigate undesirable separation of the wrist from the socket. The wrist may have an expanding coupling, such as an expanding ring, to better secure the wrist with the socket. An actuator may cause the coupling to expand outward to prevent or mitigate undesirable separation of the wrist from the socket. Alternatively or in addition, the wrist may include torque control features to prevent undesirable or premature separation of the hand from the wrist, for example when using a “quick wrist disconnect” (QWD) apparatus. A torque control method may tailor or limit multiple torques to be applied by the wrist to the hand based on operational requirements and phases, such as anticipated torque loads and operational timing.

A system and method for a compliant four-bar linkage mechanism for a robotic finger that includes: a monolithic bone structure comprised of a compliant joint region and an input link segment and a coupler link segment, wherein the input link segment and the coupler link segment are connected through the compliant joint; an output link; a ground structure; wherein the monolithic bone structure, output link, and ground structure are connected through a set of joints in a configuration of a compliant four-bar linkage mechanism which comprises: the output link on a first end and the coupler link segment connected through an output joint, the output link on a second end connected to a ground joint on the ground structure, and the monolithic bone structure connected to an input joint connected to the ground structure; and an actuation input coupled to the input joint.

Prosthetic hand (1) with a wrist (13) and provided with a hand palm (2) and fingers (4) attached to the hand palm (2), wherein the hand palm (2) and fingers (4) comprise bars (5) and joints (6) connecting the bars (5) forming a construction (7) supported by the wrist (13), wherein said bars (5) occupy a position with reference to each other de-pending on an external load applied to the construction (7), wherein a reaction force for said load applied to the construction (7) is provided by or through the wrist (13), and wherein the construction (7) has an unloaded position wherein the fingers (4) are stretched and a plurality of loaded positions corresponding to loads applied to an inner side of the hand (1) wherein the construction (7) is deflected from the unloaded position wherein the fingers (4) are stretched into a series of loaded positions in which the fingers (4) are flexed into increasingly bonded positions so as to eventually close the hand (1), and that said construction (7) is provided with a locking mechanism (9) to lock the construction (7) in one of the plurality of loaded positions.

Various embodiments of the present invention generally relate to prosthetic partial finger designs that can mimic the last two joints of the finger. Some embodiments include a proximal phalange, a distal phalange coupled to the proximal phalange, and a knuckle track (e.g., formed in an arc). The knuckle track can be moveably coupled to the proximal phalange an may include multiple teeth formed on which the proximal phalange slides along. A ratcheting mechanism can contact the multiple teeth to allow sliding in only a first direction while the ratcheting mechanism is engaged. Some embodiments include a release mechanism (e.g., a button) configured to disengage the ratcheting mechanism from the multiple teeth to allow the distal phalange to slide in a second direction. In some embodiments, the device may include a spring-back capability that automatically extends the finger after reaching full finger flexion, enabling one-handed use.

This disclosure provides systems, apparatuses, and devices for a powered prosthetic digit. The disclosed devices restore prehension in a person with missing fingers or thumb by providing motor-driven extension and flexion, and opposition to forces in the extension direction via a pawl and locking rack ratchet mechanism, thereby allowing an individual to manipulate or stabilize objects. In one embodiment, a digit comprises a base configured to be removably couplable to an anchor, a first segment pivotably coupled to the base, and a second segment removably coupled to the first segment. The first segment comprises a rack with a plurality of rack teeth and a pawl with a nose configured to engage with the rack to prevent pivoting of the first segment in a rotational direction corresponding to extension of the prosthetic digit. The second segment comprises a drive gear operable to pivot the first segment with respect to the base.

Prosthesis for at least one cut-off finger resulting in a stump at the height of the proximal, middle and/or distal phalange, or in a finger with missing stump. The prosthesis from a modular hinged mechanism allowing for a self-return flexion movement and the activation of said mechanism from at least one force applied to any point of a plane on said mechanism. A prosthesis for a hand with missing stumps is also provided from the wrist movement providing a range of operation greater than the art, wherein said flexion is activated from an extension movement of the wrist.

An under-driven prosthetic hand with a self-adaptive grasping function is provided, which belongs to the field of medical equipment. The prosthetic hand simultaneously controls four fingers to implement bending and stretching movements by a first motor through structural designs of a prosthetic hand body, a finger transmission module, an inter-finger transmission module, and a thumb driving module, and limits the transmission torque between the motor and screws using a damping shaft and in cooperation with the telescopic characteristic of a telescopic component. On the one hand, mechanical damage to the prosthetic hand structure due to excessive torque outputted by the motor can be prevented. On the other hand, the self-adaptive grasping function of the prosthetic hand can be implemented. The disclosure can also effectively solve issues such as excessive volume or mass of the prosthetic hand, complicated control system, and low operation precision.

A grasping mechanism is provided. The grasping mechanism includes a base and at least two linkage grasping assemblies. Each linkage grasping assembly includes a grasping member, a first rod and a second rod. The grasping member includes a grasping portion and a connecting portion. The first rod has a first end rotatably connected to the connecting portion and a second end rotatably connected to the base. The second rod has a first end rotatably connected to the connecting portion and a second end rotatably connected to the base. The length of a first connecting line between rotation centers of two ends of the first rod is constantly different from the length of a second connecting line between rotation centers of two ends of the second rod, or the length of the first connecting line is different from the length of the second connecting line in a certain operation state.

The disclosure provides apparatus and methods of use pertaining to a prosthetic finger assembly. In one embodiment, the assembly includes a coupling tip and a distal ring coupled with the coupling tip. The assembly further includes a proximal ring coupled with the distal ring. A rocker formed in a Y-shape with a first end forming a single prong and a second end forming a split prong may extend between the coupling tip and the proximal ring. The coupling tip, distal ring, proximal ring, and Y-shaped rocker may all be hingedly connected such that movements of the residual finger within the proximal ring and the distal articulate the distal ring together with the rocker to curl and bend the coupling tip. Other embodiments are also disclosed.

Provided are mechanisms that allow selective compliance in robot joints.